title: Investigation of the first-order phase transition in the Co(1-x)Mg(x)MoO4 solid solution and discussion of the associated thermochromic behavior.
abstract: A series of compounds of Co(1-x)Mg(x)MoO(4) compositions has been prepared by a conventional ceramic route. The members of the whole solid solution exhibit a reversible first-order phase transition which was probed by using thermal expansion and low-temperature reflectivity techniques. Whereas the α → β transition temperature evolves linearly on warming from 435 to 200 °C with x going from 0 to 0.9, the β → α transition temperature variation falls down on cooling from -40 °C to -140 °C going from CoMoO(4) to Co(0.1)Mg(0.9)MoO(4) with an asymptotic evolution. The phase transition temperatures have been explained on the basis of a crystal polarization effect under substitution of Mg for Co. Thus, from an applicative point of view, new thermochromic pigments with tunable transition temperatures are here proposed.
authors.affiliation: Université de Bordeaux, CNRS, ICMCB, Pessac Cedex, France.
authors.forename: L C
authors.initials: LC
authors.lastname: Robertson
authors.forename: M
authors.initials: M
authors.lastname: Gaudon
authors.forename: S
authors.initials: S
authors.lastname: Jobic
authors.forename: P
authors.initials: P
authors.lastname: Deniard
authors.forename: A
authors.initials: A
authors.lastname: Demourgues